A Novel Method for the Preparation of Narrow-Disperse Nanoencapsulated Phase Change Materials by Phase Inversion Emulsification and Suspension Polymerization

Narrow-disperse nanoencapsulated phase change materials with methyl methacrylate as shell material and n-octadecane as core material were successfully prepared by phase inversion emulsification and suspension polymerization. We characterized the structure, surface morphology, particle size distribution, and thermal properties of prepared nanocapsules using methods such as the Fourier infrared spectrum, scanning electron microscopy analysis, transmission electron microscopy (TEM), differential scanning calorimetry analysis, and thermogravimetric analysis. The effects of surfactant concentration and monomer/n-octadecane mass ratios on the average diameter and phase change properties of nanoencapsulated n-octadecane were investigated. The average diameter of nanocapsules is ∼300–500 nm. The surface is quite smooth and compact. An obvious core–shell structure can be observed from TEM images, and the thickness of the shell is ∼50 nm. When the n-octadecane/monomer mass ratio is 5:4, the encapsulation efficiency of the nanocapsules reaches the highest point at 52.9%.